Indication of thread breaks in textile machines



E. BREUNING 2,863,276 INDICATION 0F THREAD BREAKS IN TEXTILE MACHINES Filed June 17.4953

Dec. 9, 1958 ATTORNEYS nite Patented Dec. 9, 19555 INDICATION OF THREAD BREAKS IN TEXTILE MACHINES Ernst Breathing, Gerlingen Kreis Leonberg, Germany, as-

signor to Pneumatil Corporation, Charlotte, N. C., a corporation of Delaware Application .iune 17, 1953, Serial No. 362,331

Claims priority, application Germany June 19, 1952 12 Claims. (Cl. 5734.5)

This invention relates to improvements in the indication of thread breaks in textile machines. Thread breaks have an extremely disturbing effect in a number of textile processes, as for example, in the operation of spinning machines. It must be assured that these machines are immediately shut down when a thread break occurs. If such an immediate shut-down is not effected, a large number of spinning places on the machine will be so disturbed by even a single broken thread that their further operation will be prevented and in addition a substantial loss of material will be caused.

Various arrangements have already been suggested to effect the indication and/or shut-down of the machine upon the occurrence of a thread break.

In accordance with one proposal, a conventional thread suction device is utilized. This may, for example, consist of a pipe through which air is continuously drawn. The suction device will suck in and thus remove the broken thread and thus keep it from fouling the other spinning places. This, however, will not shut down the spinning machine or actuate a positive signal or alarm. The operator of the machine who customarily has to take care of a number of such machines may not notice the break and hundreds of feet of thread may be lost in the suction channel by the time the operator finally notices the thread break and stops the machine.

In accordance with another proposal, deviations from a prescribed path of travel of the thread are optically indicated by photoelectric cells or electrically indicated by the broken thread closing an electric circuit. This, however, does not prove the practical solution to the problem inasmuch as the devices utilized do not meet the requirements of practical operation and are often effected by dust and unavoidably flying fibers. In addition, these devices are relatively costly in both initial installation and maintenance.

In another known device, a screen sieve is movably arranged in the channel of a thread suction device of a spinning machine and acts as the control element. When a thread is broken it is drawn off by the thread suction device and comes in contact with the screen sieve thus clo ing at least a portion of the opening of the latter and in this way producing an increase in the pressure in the part of the channel located in front of the screen sieve as compared with the pressure in back of the sieve. This increase in pressure may be utilized by means of a manometer through levers and pushrods etc. to stop the spinning machine or for optically or acoustically indicating the thread break.

After the occurrence of a thread break and the actua-- tion of the signal or stop mechanism, the screen sieve must be cleaned of the threads in order to reset the same into a condition of readiness to indicate etc. further thread breaks. This cleaning could not be satisfactorily effected with the conventional screen sieves which consisted of perforated disks. The device, therefore, was never successfully accepted for practical operation.

One object of this invention is a device supervising and controlling textile machines by indication of any thread break and possibly by automatically shutting down the textile machine upon the occurrence of such a thread break.

A further object of this invention is an improved construction for a device utilizing a screen sieve in the channel of a thread suction device of a spinning machine for supervising and controlling the machine which avoids all the disadvantages previously encountered. These and still further objects will become apparent from the following description read in conjunction with the drawing in which:

Fig. 1 diagrammatically shows a cross section of an embodiment of a device in accordance with the invention, and

Fig. 2 shows a front elevation of an embodiment of a thread sieve in accordance with the invention.

In accordance with the invention, a thread sieve is movably positioned in the pipeline of a thread suction system. The thread sieve in accordance with the invention is developed in the form of a rake having a number of parallel, spaced-apart member such as parallel bars, pipes, rails or the like, the ends of which are free. This development of the thread sieve for the first time makes possible the removal of the fibers or portions of the thread adhering to the thread sieve with the use of the suction air itself. As contrasted to this in the conven tional devices using the conventional thread sieves, threads, fibers, etc. would penetrate so far into the perforations of the sieve that they could no longer be removed and carried along by the suction air.

The "thread sieve in accordance with the invention may be utilized in the conventional manner in which the broken thread or sliver or parts thereof increasingly closes the openings of the sieve thus bringing about a pressure differential on each side of the sieve and a drop of the air pressure behind the sieve which may be utilized by known means, as for example, a manometer to indicate the break of the thread or sliver and/or to stop the textile machine. I

In accordance with a preferred embodiment of the invention, the thread sieve is pivotally mounted within the pipeline so that when, in its rest position, it partially closes the pipeline and is pivoted upward out of its closed position by the impact against it by the broken thread or sliver or parts thereof. This pivoting out of the closed position by impact i utilized in accordance with the invention, to actuate a mechanical and/or electrical relay which in turn, by known means, gives an indication of the break or sliver and/or stops the textile machine.

It has further been found that the dependability of the supervision and control of textile machinery with respect to breaks of threads or slivers is impaired to a large extent by an increasing closure of the openings of the thread sieve due to individual fibers which are unavoidably drawn into the pipeline of the thread suction system. These fibers build up and may effect erroneous indications or undesirable stoppages of the machines.

In accordance with a further embodiment of the inven tion in order to avoid the above mentioned drawback, the individual fibers are periodically cleaned preferably automatically from the thread sieve at time intervals which are greater than the longest interval of time which is required for the closing of the passage of the thread sieve by a broken thread, etc. This, for example, may be effected by means which periodically swing the thread sieve out of its closed position and allows the suction air to clean the same While, at the same time, disconnecting the actuation mechanism which gives an indication of the break of thread or sliver and/ or stops the textile machine,

The invention will be described in further detail with reference to one embodiment thereof as shown in the drawing.

The pipe section 1 of a thread suction system is provided with a bend at the place 2. Atthis place, there is arranged the thread sieve 3 which is developed as a hinge movable around the pin 5. The baffie plate 4 is provided to divert the drawn-01f air and thus keep the '1 pin 5 clean. The thread sieve 3, developed as a rake, consists of the fastening member 7 and the parallel bars 6 which, in accordance with the present invention, taper down to their free ends. In the closed position of the thread sieve 3, the ends of the bars 6 rest on the bead 8 of the wall of pipe section 1 of the thread suction system. The electromagnet 9 serves to hold the thread sieve 3, consisting of magnetic material, as for example, iron 'against the wall of pipe section 1. On the fastening member 7 of the thread sieve 3, there is arranged a resilient contact 10. A mating contact 11 is provided in the tube section 1. Both of these contacts, in accordance with the present embodiment, are arranged in the circuit of an electric relay which, in its turn, signals the thread or sliver break and/ or stops the textile machine.

The manner of operation of the device shown is as follows: If a thread or a sliver breaks, they or parts of them pass through the thread suction system in the direc tion indicated by the arrow into the pipe section 1, where they come against the thread sieve 3 which is in its closed position.

There are two possible methods of signalling the thread break and/ or stopping the textile machine by means of the thread sieve which serves as control element.

In accordance with the first method of operation of the thread sieve, the attraction force of the electromagnet 9 which holds the thread sieve in closed position is so adjusted, for example, by regulating the excitation current, that this attraction force is only overcome after, due to the increasing closure of the passage openings of the thread sieve 3, there takes place in the pipeline of the thread suction system a pressure drop which is utilized in the known manner manometrically to signal the thread break or to stop the textile machine.

In accordance with the second method of operation, the attraction force exerted by the electromagnet 9 and which holds the thread sieve in the closed position is adjusted in such a manner that this pulling force is overcome by the impact caused by the thread which has been drawn in as a result of the break of a thread.

In the first case, the thread sieve acts manometrically as control element in the known manner, while in the second case its action is characterized by the fact that it is immediately brought out of its closed position when hit by a broken thread, due to the fact that the contacts 10 and 11 touch each other and in this way the relay circuit effecting the signal or stopping of the textile machine is closed.

In both cases, however, it is obtained by the development of the thread sieve of the present invention that this sieve is freed of the drawn-in threads after it has performed its proper function inasmuch as these threads or thread parts are stripped off from the free ends of the bars or the like by the suction air and carried along with the latter. The dependability of this absolutely necessary cleaning may be still further increased by having the ends of the bars or the like tapered as shown.

A further improvement in accordance with the present invention is, furthermore, obtained by having the thread sieve so dimensioned, as for example, by imparting it a suitable shape or by determining its weight with reference to the suction force of the thread suction system that the bars or the like do not form any angle with the axis of the suction air fiow when they are in the open position, or at least only form a small angle with said axis.

Furthermore, the dependability of the operation in accordance with the present invention, is still further st1bstantially improved by the fact that known switch members located in the excitation circuit of the electromagnet 9, for example, contacts which are actuated by the opening notice of the thread sieve, reduce or overcome at the beginning of the opening motion, the force holding the thread sieve in the closed position.

Inasmuch as even when there is no thread break, fibers are drawn away by the thread suction plant continuously .in a very small quantity, these fibers over the course of time can close the passage openings of the thread sieve 3 and bring about a false indication of a thread break or an undesired stoppage of the textile machine. In accordance with a further characteristic of the invention, there is proved an interrupter for the excitation current of the electromagnet 9 which interrupts this current for a short period of time at preferably periodic time intervals and at the same time, the actuation of the switching devices resulting in the thread break signal and/or the stopping of the textile machine is prevented by known switch elements. The interrupter may be of any known conventional construction.

In this way, there is obtained a periodic cleaning of the thread sieve 3 so that the actuation of the thread break signal and/or the stopping of the textile machine only results when a thread or sliver break has actually occurred.

Furthermore, in accordance with the present invention, instead of utilizing electromagnetic forces, there may also be used pneumatic, hydraulic or spring forces for the actuation of individual functions required for the carrying out of the method of the present invention.

In the specification, the term supervision means will be used to generically designate any of the known means for signalling and/ or stopping the textile machine when actuated either electrically or mechanicallly etc.

I claim:

1. In a device for the supervision and control of textile machinery having a thread sieve positioned in the i eline of a thread suction arrangement, the improvement which comprises said thread sieve comprising a rake having a multiple number of substantially parallel, freeended bar members movably mounted in said pipeline for movement between a closed position with said bar members extending substantially across the entire cross section of said pipeline and an open position with said bar members extending substantially in the direction of the flow axis of said pipeline said rake having at least a portion thereof of magnetic material and an electromagnet positioned for the magnetic attraction of said magnetic material to maintain said rake in said closed position with a predetermined force.

2. Improvement according to claim 1 in which said bar members are fastened at one end to a fastening member and in which said fastening member is pivotably connected on one side of said pipeline.

3. Improvement according to claim 1 including means for actuating supervision means for the textile machinery upon movement of said rake from said closed position toward said open position.

4. Improvement according to claim 3 in which said means for actuation of the supervision means includes a movable electric contact connected to said rake and a fixed electric contact positioned for contact with said movable electric contact upon movement of said rake from said closed position toward said open position.

5. Improvement according to claim 1 including means for actuating supervision means for the textile machinery upon an increase in the drop of air pressure in said pipeline behind said rake.

6. Improvement according to claim 1 in which the free ends of the bar members of said rake are tapered.

7. Improvement according to claim 6 in which said bar members are fastened at one end to a fastening member and in which said fastening member is pivotably connected on one side of said pipeline.

8. Improvement according to claim 1 including means for periodically de-energizing said electromagnet to allow said rake to move from said closed position to said open position for the automatic cleaning thereof.

9. Improvement according to claim 1 including means for deenergizing said electromagnet upon actuation of supervision means for the textile machinery.

10. Improvement according to claim 1 including means for deenergizing said electromagnet by breaking the circuit thereof upon movement of said rake from said closed toward said open position.

11. Improvement to claim 1 including means for periodically re-energizing said electromagnet and simultanerake is of magnetic material and in which said electro-,

magnet is positioned for attraction of the free ends of said bar members in the closed position of said rake.

References Cited in the file of this patent UNITED STATES PATENTS 1,042,394 Cheesman Oct. 29, 1912 1,056,260 Cheesman Mar. 18, 1913 2,500,343 Carrette Mar. 14, 1950 UNITED STATES PATENT'OFFICE CERTIFICATE OF CORRECTION Patent Nm 2,863,276

December 9, 1958 Ernst Breuning that error appears in the printed specification requiring correction and that the said. Letters read as corrected below,

0011111111.! line 14,

for "proved read provided for re==energizing" column 5, line 13, read deenergizing Signed and sealed this 24th day of February 1959.

(SEAL) Attest: KARL Ho AXLINE ROBERT C. WATSON Attesting- Officer rmiissioner of Patents 

